An all-wheel driven motor vehicle of the kind mentioned above has been disclosed in German Patent 29 33 267. The gear change of this field tractor has a rear-mounted range change group with an overdrive for transportation speed in which the field tractor must generally be operated with front-wheel drive. A gear of an axle reduction situated between the output shaft and the bevel-pinion shaft is connected, when working in arable land, with the bevel-pinion shaft via a positive locked clutch. Simultaneously with the actuation of the overdrive, said positive locked clutch is released via a connecting linkage. Favorable traction values can be obtained in heavy traction works of the field tractor in arable land only with permanent all-wheel drive, the rigid connection between front and rear axles having a negative effect when the field tractor corners. The problem consists in that the front wheels, as a result of the larger radius of curve needed for maintaining traction, must rotate quicker than the rear wheels. Due to the equal axle speeds, the front wheels are pushed when cornering so that, as a consequence of the increased slip, the traction of the field tractor cannot be utilized and serious warping of the soil also appears as well as an enlarged radii of turn of the field tractor.